i had a similar issue with my 3.9 v6. we thought it was a lifter or broken exhaust stud, as mentioned above, but eventually we found it was a HOLE in the EXHAUST MANIFOLD on the passenger side. Michigan will do that.

 

My father is a Chrysler engine engineer and this is what he had to say:

"At 160,000 miles the 4.7 liter silent timing chains may be worn. If the tick is on the passenger side cylinder head at the front, remove the black plastic oil fill housing. Four M6 bolts should hold that housing to the front of the head. Start the engine and let it idle. With a large straight edge screwdriver, gently pry up the timing chain tensioner arm with the engine idling. Tf the tick stops, your chain is worn excessively. The chain tensioner could be defective too, but more likely the chain is worn at that mileage."

 

its a 8mm not a 6. trust me, i didnt bolt it down all the way and blew my motor that way.

 

Hmm
I can try that. The dealer said it's the valves